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High-resolution Nuclear Magnetic Resonance ( NMR) spectroscopy has many applications in the analysis of food and beverage products, especially in combination with multivariate analysis. Most studies have focused on the composition, raw materials, geographical origin, and quality control of these products. Since the 1H NMR spectrum of beer contains huge water and ethanol resonances with higher signal intensities of them than those of the compounds of interest, it becomes problematic to assign a spectrum. So, these obstacles must be overcome in order to define chemical components in beer and to analyze or obtain meaningful data. In this paper, we will analyze the 1H NMR spectra of different lagers and ales with principal component analysis ( PCA) and partial least squares ( PLS) methods. The results of multivariate analysis of 1H NMR spectra of lyophilized and raw samples obtained using a standard solvent suppression pulse program are compared and discussed for more exact technique as an informative quality control tool. [ABSTRACT FROM AUTHOR]

2-Periodic self-dual tilings are important in fields ranging from crystal chemistry to mathematical physics. They have been systematically enumerated using combinatorial tiling theory, and 1, 5 and 62 uninodal, binodal and trinodal self-dual tilings have been found. This paper illustrates all uninodal and binodal self-dual tilings and selected trinodal self-dual tilings. Most of these structures are described for the first time. [ABSTRACT FROM AUTHOR]

Global Positioning System (GPS) surface reflected signals have previously been studied for aircraft passive bistatic altimetry and remote sensing. In this research, GPS reflected measurements from a software-defined receiver (SDR) are used for aircraft passive bistatic altimetry and coasting with a Stable Frequency Reference (SFR) to continue navigation when only two GPS satellites are available. The research in this paper focuses on flights over water, a scenario in which the water causes strong reflected signals while alternate terrestrial radio navigation signals are generally not available. Theoretical clock and position error covariances are derived as a function of measurement error, satellite geometry, SFR stability, and GPS bistatic altimetry performance. This is followed by computer simulations and evaluations using flight test data to characterize the positioning performance. Copyright © 2017 Institute of Navigation [ABSTRACT FROM AUTHOR]

In this paper we study local existence, uniqueness, and continuous dependence of an abstract integrodifferential equation. We also present a result on unique continuation and a blow-up alternative for mild solutions of the integrodifferential equation. Finally, we apply our results to an interesting strongly damped plate equation with memory. [ABSTRACT FROM AUTHOR]

In this paper, we study second order linear Sturm-Liouville problems involving one or two homogeneous linear multi-point boundary conditions in the most general form. We obtain conditions for the existence of a sequence of positive eigenvalues with consecutive zero counts of the eigenfunctions. Furthermore, we reveal the interlacing relations between the eigenvalues of such Sturm-Liouville problems and those of Sturm-Liouville problems with certain two-point separated boundary conditions. [ABSTRACT FROM AUTHOR]

We give a sharp estimate for the codimension of the poly-Bergman space in the poly-Bergman space over the punctured domain. It is established the behaviour at the infinity point of polyanalytic Bergman functions on the complement of closed disks. In the main result of the paper, we prove that for [ABSTRACT FROM AUTHOR]

A method is proposed to generate an isolated attosecond X-ray pulse in free-electron lasers, using irregularly spaced current peaks induced in an electron beam through interaction with an intense short-pulse optical laser. In comparison with a similar scheme proposed in a previous paper, the irregular arrangement of current peaks significantly improves the contrast between the main and satellite pulses, enhances the attainable peak power and simplifies the accelerator layout. Three different methods are proposed for this purpose and achievable performances are computed under realistic conditions. Numerical simulations carried out with the best configuration show that an isolated 7.7 keV X-ray pulse with a peak power of 1.7 TW and pulse length of 70 as can be generated. In this particular example, the contrast is improved by two orders of magnitude and the peak power is enhanced by a factor of three, when compared with the previous scheme. [ABSTRACT FROM AUTHOR]

This paper studies the distributed average computation problem for multiple time-varying signals with bounded inputs. Based only on relative output measurements, a pair of continuous algorithms with, respectively, static and adaptive coupling strengths are designed and utilized. From the concept of boundary layer approach, the proposed continuous algorithm with static coupling strengths can asymptotically obtain the average value of the multiple reference signals without chattering phenomenon. Furthermore, for the case of algorithms with adaptive coupling strengths, the calculation errors are uniformly ultimately bounded and exponentially converge to a small adjustable bounded set. Finally, a simulation example is presented to show the validity of the theoretical results. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

SUMMARY This paper investigates the problem of distributed reliable H ∞ consensus control for high-order networked agent systems with actuator faults and switching undirected topologies. The Lipschitz nonlinearities, several types of actuator faults, and exogenous disturbances are considered in subsystems. Suppose the communication network of the multi-agent systems may switch among finite connected graphs. By utilizing the relative state information of neighbors, a new distributed adaptive reliable consensus protocol is presented for actuator failure compensations in individual nodes. Note that the Lyapunov function for error systems may not decrease as the communication network is time-varying; as a result, the existing distributed adaptive control technique cannot be applied directly. To overcome this difficulty, the topology-based average dwell time approach is introduced to deal with switching jumps. By applying topology-based average dwell time approach and Lyapunov theory, the distributed controller design condition is given in terms of LMIs. It is shown that the proposed scheme can guarantee that the reliable H ∞ consensus problem is solvable in the presence actuator faults and external disturbance. Finally, two numerical examples are given the effectiveness of the proposed theoretical results. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Accounts of Hobbes's 'system' of sciences oscillate between two extremes. On one extreme, the system is portrayed as wholly axiomatic-deductive, with statecraft being deduced in an unbroken chain from the principles of logic and first philosophy. On the other, it is portrayed as rife with conceptual cracks and fissures, with Hobbes's statements about its deductive structure amounting to mere window-dressing. This paper argues that a middle way is found by conceiving of Hobbes's Elements of Philosophy on the model of a mixed-mathematical science, not the model provided by Euclid's Elements of Geometry. I suggest that Hobbes is a test case for understanding early-modern system construction more generally, as inspired by the structure of the applied mathematical sciences. This approach has the additional virtue of bolstering in a novel way the thesis that the transformation of philosophy in the long seventeenth century was indebted to mathematics, a thesis that has come under increasing scrutiny in recent years. [ABSTRACT FROM AUTHOR]

In this paper, we describe some necessary and sufficient conditions for a set of coboundaries to yield a cocyclic Hadamard matrix over the dihedral group [ABSTRACT FROM AUTHOR]

In this paper, we determine the necessary and sufficient conditions for the existence of an equitably ℓ-colorable balanced incomplete block design for any positive integer [ABSTRACT FROM AUTHOR]

In this paper we give characterizations of the stable and ℵ0-stable theories, in terms of an external property called representation. In the sense of the representation property, the mentioned classes of first-order theories can be regarded as 'not very complicated'. [ABSTRACT FROM AUTHOR]

As far as algebraic properties are concerned, the usual addition on the class of ordinal numbers is not really well behaved; for example, it is not commutative, nor left cancellative etc. In a few cases, the natural Hessenberg sum is a better alternative, since it shares most of the usual properties of the addition on the naturals. A countably infinite iteration of the natural sum has been used in a recent paper by Väänänen and Wang, with applications to infinitary logics. We present a detailed study of this infinitary operation, showing that there are many similarities with the ordinary infinitary sum, providing an order theoretical characterization, and finding connections with certain kinds of infinite mixed sums. [ABSTRACT FROM AUTHOR]

In this paper, the positive fragment of the logic [ABSTRACT FROM AUTHOR]

In this paper we prove that the first order theories of the free MV algebras with finitely many generators are different from each other. This answers to the MV algebra analogue of a well-known (now solved) problem of Tarski for groups. [ABSTRACT FROM AUTHOR]

Despite several scholars referring to the relationships between the philosophy of Boltzmann and Wittgenstein, this topic is still to be explored. The aim of this paper is to analyse the similarities between their views on mathematical continuum and on the meaning of physical theories and phenomenological states of affairs. In several arguments, they both aim to achieve a similar task: by clarifying the meaning of theories in their concrete use, both authors persuade the reader to abandon an apparently intuitive way of thinking in order to overcome theoretical problems by dissolving them. [ABSTRACT FROM AUTHOR]

A common claim about mathematics education is that it should equip students to use mathematics in the ‘real world’. In this paper, we examine how relationships between mathematics education and the real world are materialised in the curriculum across a sample of eleven jurisdictions. In particular, we address the orientation of the curriculum towards application of mathematics, the ways that real-world contexts are positioned within the curriculum content, the ways in which different groups of students are expected to engage with real-world contexts, and the extent to which high-stakes assessments include real-world problem solving. The analysis reveals variation across jurisdictions and some lack of coherence between official orientations towards use of mathematics in the real world and the ways that this is materialised in the organisation of the content for students. [ABSTRACT FROM PUBLISHER]

In 1998 the second author proved that there is an ε > 0 such that every graph satisfies ≤ [(1 - ε)(Δ+ 1) + εω]. The first author recently proved that any graph satisfying ω > 23 (Δ + 1) contains a stable set intersecting every maximum clique. In this note, we exploit the latter result to give a much shorter, simpler proof of the former. Working from first principles, we omit only some five pages of proofs of known intermediate results (which appear in an extended version of this paper), and the proofs of Hall's Theorem, Brooks' Theorem, the Lovász Local Lemma, and Talagrand's Inequality. [ABSTRACT FROM AUTHOR]

This paper presents the results of a multi-method study examining elementary students with high self-reported levels of mathematics motivation. Second- through fifth-grade students at a Title One school in the southeastern United States completed the Elementary Mathematics Motivation Instrument ( EMMI), which examines levels of mathematics motivation across three subscales: (a) Math Anxiety, (b) Self-Efficacy, and (c) Value of Math. Results from this quantitative phase were used to identify a sample for a qualitative phase examining how students who report high levels of motivation perceive mathematics. The resulting qualitative phase utilized a phenomenological design to explore mathematics motivation for a particular set of students in a fifth-grade setting. Findings indicate that elementary students with high mathematics motivation value mathematics as a present and future oriented discipline and value teachers that deemphasize testing as a measure of success. [ABSTRACT FROM AUTHOR]

In this paper, we obtain some new Lyapunov-type inequalities for a class of even-order linear differential equations, the results are new and generalize and improve some early results in this field. [ABSTRACT FROM AUTHOR]

This paper investigates stability of nonlinear control systems under intermittent information. Following recent results in the literature, we replace the traditional periodic paradigm, where the up-to-date information is transmitted and control laws are executed in a periodic fashion, with the event-triggered paradigm. Building on the small gain theorem, we develop input-output triggered control algorithms yielding stable closed-loop systems. In other words, based on the currently available (but outdated) measurements of the outputs and external inputs of a plant, a mechanism triggering when to obtain new measurements and update the control inputs is provided. Depending on the noise in the environment, the developed algorithm yields stable, asymptotically stable, and [ABSTRACT FROM AUTHOR]

This paper presents a comparison of three approaches to the teaching of probability to demonstrate how the truth table of elementary mathematical logic can be used to teach the calculations of conditional probabilities. Students are typically introduced to the topic of conditional probabilities-especially the ones that involve Bayes' rule-with the help of such traditional approaches as formula use or conversion to natural frequencies. The truth table approach is an alternative method for explaining the concept and calculation procedure of conditional probability and Bayes' rule. [ABSTRACT FROM AUTHOR]

In this paper, we establish the existence and non-existence of positive solutions for p-Kirchhoff type problems with a parameter on [ABSTRACT FROM AUTHOR]

Computer-assisted instruction ( CAI) programs are considered as a way to improve learning outcomes of students. However, little is known on the schools who implement such programs as well as on the effectiveness of similar information and communication technology programs. We provide a literature review that pays special attention to the existing causal evidence of computer-assisted programs on learning outcomes. The paper relies on a rich data set consisting of (i) pupil-level information on the use of a Dutch computer-assisted program and (ii) detailed school-level information on, among others, outcomes on national exams. The results suggest that schools with lower educational attainments use more frequently CAI programs. This suggests that they use CAI programs to catch up on learning outcomes. Moreover, using an instrumental variable design, we argue that given the participation in the CAI program, making more exercises leads to higher test results. Working with a CAI program seems therefore effective. [ABSTRACT FROM AUTHOR]

Mitochondria can change their shape from discrete isolated organelles to a large continuous reticulum. The cellular advantages underlying these fused networks are still incompletely understood. In this paper, we describe and compare hypotheses regarding the function of mitochondrial networks. We use mathematical and physical tools both to investigate existing hypotheses and to generate new ones, and we suggest experimental and modelling strategies. Among the novel insights we underline from this work are the possibilities that (i) selective mitophagy is not required for quality control because selective fusion is sufficient; (ii) increased connectivity may have non-linear effects on the diffusion rate of proteins; and (iii) fused networks can act to dampen biochemical fluctuations. We hope to convey to the reader that quantitative approaches can drive advances in the understanding of the physiological advantage of these morphological changes. [ABSTRACT FROM AUTHOR]

This paper describes how to analyse translinear topologies whose response is modified by the body effect by means of the general translinear principle. It proposes two different strategies for obtaining the translinear loop equations from each closed translinear set. Both strategies are tested analysing three topologies, one of them including some transistors in triode. From the results of such analysis, a fast analysis method for topologies with all transistor bodies connected to the same potential is also proposed. Simulated results are given showing good agreement with theoretical expressions. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Fidelity of curriculum implementation (FOI) is an important area of research because of the critical role it plays in understanding how and why curriculum materials work and how they can be improved. This analysis explores written features within the Math Trailblazers curriculum that may influence the ways teachers implement mathematics curriculum materials. In particular, we examine FOI data from prior research in order to identify features within the materials themselves that may influence why teachers adhere to the intended curriculum to varying degrees. This paper reports on our analysis of examining five whole number lessons previously analysed for level of FOI alongside an analysis scale of written curriculum features. Our purpose in this analysis is to examine features of the written curriculum that potentially mediate teachers’ implementation of the materials in line with the intended curriculum. In doing so, our analysis further emphasises the critical role teachers play in curriculum implementation, and thus may provide some insight for curriculum developers as they consider ways in which to design the written curriculum that increase the likelihood that teachers will adhere to the intended curriculum. [ABSTRACT FROM PUBLISHER]

The main result of this paper is Theorem [1.1], which shows that it is possible for derived models to satisfy [ABSTRACT FROM AUTHOR]

Here we study properties of weakly circularly minimal cyclically ordered groups. The main result of the paper is that any weakly circularly minimal cyclically ordered group is abelian. [ABSTRACT FROM AUTHOR]

Transforming a dynamical system by adding auxiliary dynamics is one of the most recent tools to design an observer. Dynamical systems that have the properties of admitting such transformation have been widely studied. Indeed, in the existing literature, several different types of geometrical and analytical characterizations of such dynamical systems have been established. However, one finds only a few examples on this topic. Therefore, the main focus of this paper is to characterize a class of single-output dynamical systems that can be transformed by means of a change of coordinates into an extended nonlinear observer normal form. Furthermore, this class provides examples of systems that can be transformed adding to them more than one auxiliary dynamics. To our knowledge, examples on this last fact lack in the existing research literature on this topic. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In this paper, we consider the consensus problem for heterogeneous multi-agent systems composed of some first-order and some second-order dynamic agents in directed communication graphs. Consensus protocols are proposed for the second- and first-order dynamic agents, respectively. Under certain assumptions on the control parameters, for fixed communication topologies, necessary and sufficient conditions for consensus are given, and the consensus values of all agents are established. For switching topologies, sufficient conditions are given for all agents to reach consensus. Finally, simulation examples are presented to demonstrate the effectiveness of the proposed methods. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Metal welding structural strength was affected by the quality of automobile welding structure. Many accidents of the machines are caused by welding defects of automobile structure. Many welding parts are applied in the automobile. Reliability of automobile welding structure is studied and discussed in this paper. Failure modes and ultimate strength of automobile welding structure are obtained with bench test. The results show that all the failures happen in the welded region between clutch hub and clutch hub axle. Finite element model is built, and automobile welding structural strength is analyzed. And simulation results are in line with that of the experiment. Based on stress and strength interference model, automobile welding structure reliability is studied and discussed with theory of probability and reliability. In accordance with matching working load with structural strength, a new method of improvement design is proposed with the aim of automobile welding structural strength reliability. It provides a theoretical basis for automobile welding structure improvement design. And similar methods can be used to develop automobile welding structure and laser welding processes in future. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In most of the linear homogenization problems involving convolution terms so far studied, the main tool used to derive the homogenized problem is the Laplace transform. Here we propose a direct approach enabling one to tackle both linear and nonlinear homogenization problems that involve convolution sequences without using Laplace transform. To illustrate this, we investigate in this paper the asymptotic behavior of the solutions of a Stokes-Volterra problem with rapidly oscillating coefficients describing the viscoelastic fluid flow in a fixed domain. Under the almost periodicity assumption on the coefficients of the problem, we prove that the sequence of solutions of our ϵ-problem converges in L2 to a solution of a rather classical Stokes system. One important fact is that the memory disappears in the limit. To achieve our goal, we use some very recent results about the sigma-convergence of convolution sequences. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In this paper, we consider the inverse problem of determining the heat source, which depends only on spatial variable in one-dimensional heat equation in a bounded domain where data is given at some fixed time. A conditional stability result is given, and a quasi-boundary value regularization method is also provided. For this regularization solution, the Hölder type stability estimate between the regularization solution and the exact solution is obtained. Numerical examples show that the regularization method is effective and stable. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In this paper, we are concerned with the existence of infinitely many solutions for the following fractional Hamiltonian systems [ABSTRACT FROM AUTHOR]

In this paper, we concentrate on the maximal inclusion problem of locating the zeros of the sum of maximal monotone operators in the framework of proximal point method. Such problems arise widely in several applied mathematical fields such as signal and image processing. We define two new maximal monotone operators and characterize the solutions of the considered problem via the zeros of the new operators. The maximal monotonicity and resolvent of both of the defined operators are proved and calculated, respectively. The traditional proximal point algorithm can be therefore applied to the considered maximal inclusion problem, and the convergence is ensured. Furthermore, by exploring the relationship between the proposed method and the generalized forward-backward splitting algorithm, we point out that this algorithm is essentially the proximal point algorithm when the operator corresponding to the forward step is the zero operator. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Continuing the study of bounded geometry for Riemannian foliations, begun by Sanguiao, we introduce a chart-free definition of this concept. Our main theorem states that it is equivalent to a condition involving certain normal foliation charts. For this type of charts, it is also shown that the derivatives of the changes of coordinates are uniformly bounded, and there are nice partitions of unity. Applications to a trace formula for foliated flows will be given in a forthcoming paper. [ABSTRACT FROM AUTHOR]

In this paper we introduce the notion of decomposability in the space of Henstock-Kurzweil-Pettis integrable (for short HKP-integrable) functions. We show representations theorems for decomposable sets of HKP-integrable or Henstock integrable functions, in terms of the family of selections of suitable multifunctions. [ABSTRACT FROM AUTHOR]

Agglomeration and network externalities are fuzzy concepts. When different meanings are (un)intentionally juxtaposed in analyses of the agglomeration/network externalities-menagerie, researchers may reach inaccurate conclusions about how they interlock. Both externality types can be analytically combined, but only when one adopts a coherent approach to their conceptualization and operationalization, to which end we provide a combinatorial typology. We illustrate the typology by applying a state-of-the-art bipartite network projection detailing the presence of globalized producer services firms in cities in 2012. This leads to two one-mode graphs that can be validly interpreted as topological renderings of agglomeration and network externalities. [ABSTRACT FROM AUTHOR]

In this paper we construct inner-outer factorizations of transfer functions governed by linear time-invariant differential-algebraic systems. This construction is based on the solution of certain Lur'e equations. In contrast to previous work we do not assume any condition apart from behavioral stabilizability of the underlying system realization. (© 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

Mathematical software is of increasing importance in teaching activities, research, industry and daily life. But searching and finding information about relevant mathematical software is a non-trivial task. swMATH [1] is a new and comprehensive information service on mathematical software and mathematical research data. It contains information on nearly 13.000 software packages with more than 120.000 references to scientific articles citing the software. It offers free access to information on software in all mathematical subjects from large general purpose systems to small packages and includes benchmarks, languages, data sets, and web services, too. The paper starts with a short description of our approach and addresses some open problems for the further development. (© 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

Parrondo's paradox, in which losing strategies can be combined to produce winning outcomes, has received much attention in mathematics and the physical sciences; a plethora of exciting applications has also been found in biology at an astounding pace. In this review paper, the authors examine a large range of recent developments of Parrondo's paradox in biology, across ecology and evolution, genetics, social and behavioral systems, cellular processes, and disease. Intriguing connections between numerous works are identified and analyzed, culminating in an emergent pattern of nested recurrent mechanics that appear to span the entire biological gamut, from the smallest of spatial and temporal scales to the largest—from the subcellular to the complete biosphere. In analyzing the macro perspective, the pivotal role that the paradox plays in the shaping of biological life becomes apparent, and its identity as a potential universal principle underlying biological diversity and persistence is uncovered. Directions for future research are also discussed in light of this new perspective. [ABSTRACT FROM AUTHOR]

Buttar, H. M. (2015). Formation of entrepreneurial career intentions: The role of sociocognitive factors. Journal of Employment Counseling, 52, 2-17. doi:10.1002/j.2161-1920.2015.00052.x The above article from the Journal of Employment Counseling, published online on 2 March 2015 in Wiley Online Library (), has been retracted by agreement between the author, the journal Editor in Chief, Dale S. Furbish, and Wiley Periodicals, Inc. on behalf of the American Counseling Association. This retraction has been agreed upon because of concerns regarding authorship and methodological errors within the article. The paper was submitted without the knowledge or consent of collaborators who had contributed to earlier versions of the study. The methodological flaws resulted from omitting data that were part of a wider research report, and inappropriately using statistics that were calculated from the entire data set. [ABSTRACT FROM AUTHOR]

We report a new headspace analytical method in which multiple headspace extraction is incorporated with the full evaporation technique. The pressure uncertainty caused by the solid content change in the samples has a great impact to the measurement accuracy in the conventional full evaporation headspace analysis. The results (using ethanol solution as the model sample) showed that the present technique is effective to minimize such a problem. The proposed full evaporation multiple headspace extraction analysis technique is also automated and practical, and which could greatly broaden the applications of the full-evaporation-based headspace analysis. [ABSTRACT FROM AUTHOR]